The active compound, ingenol 3-(3,5-diethylisoxazole-4-carboxylate), of the present invention is previously been described in PCT/DK2011/000154. The ingenol 3-(3,5-diethylisoxazole-4-carboxylate) is studied with respect to safety and tolerability for field therapy in 25 cm2 on 4 separate areas on the forearm in concentrations of 0.025%, 0.05% and 0.075% in a gel formulation.
Existing topical treatments for actinic keratosis comprises different dosage regimens. All of them extend over weeks and months. Picato® which is launched in many countries around the world for treatment of actinic keratosis has a dosage regimen of two or three days depending on the location of the actinic keratosis and also the concentration of the active compound differs depending on the location of the actinic keratosis. According to the FDA label for Picato®, the size of the treatment area is limited to about 25 cm2 (2 inches×2 inches).